The visions of John come from God. Those of mohammed come from somewhere else.
W/o John's visions, we would have very little idea of what Heaven is like; nor would we know what is coming to planet earth in what the old prophets called the time of Jacob's trouble, and what Jesus Himself called "Great Tribulation, such as the world has never seen, nor will ever see again."
Add to that, John was right, mohammed was wrong.
You are expressing an opinion.
We have, for example, according to Wikipedia:
Revelation was the last book to be accepted into the Christian biblical canon, and even at the present day some Nestorian churches reject it. It was tainted because the heretical sect of the Montanists relied on it and doubts were raised over its Jewishness and authorship, and it was not until 419 that it was included in the canon.